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Linux logical volume manager: basic logic, configuration and usage

"For this Linux lvm example you need a unpartitioned
hard disk /dev/sdb. First you need to create physical volumes. To
do this you need partitions or a whole disk. It is possible to run
pvcreate command on /dev/sdb, but I prefer to use partitions and
from partitions I later create physical volumes....

"Create Virtual Group
At this stage you need to create a virtual group which will serve
as a container for your physical volumes. To create a virtual group
with the name "mynew_vg" which will include /dev/sdb1 partition,
you can issue the following command:"